The hydroxyl radical (*OH) plays a central role in the oxidation and removal of many atmospheric compounds. Measurement of atmospheric *OH is very difficult because of its high reactivity and low atmospheric abundance. In this article, a simple and highly sensitive method, high performance liquid chromatography coupled with coulometric detection (HPLC-CD), was developed to determine *OH indirectly by determining its reaction products with salicylic acid (SAL), 2,3-dihydroxybenzoic acid (2,3-DHBA), and 2,5-dihydroxybenzoic acid (2,5-DHBA). Under the optimum conditions for its determination, 2,3-DHBA and 2,5-DHBA could be well separated and the detection limits for 2,3-DHBA were 3 x 10(-10) mol/L and for 2,5-DHBA were 1.5 x 10(-10) mol/L, which were lower than most previous reports. This method was also applied to measure atmospheric hydroxyl radical levels and demonstrated the feasibility in clean and polluted air.
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http://dx.doi.org/10.1016/s1001-0742(08)60003-0 | DOI Listing |
Environ Sci Technol
January 2025
State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, P. R. China.
Beyond their roles in adsorbing and transporting pollutants, microplastics (MPs) and nanoplastics (NPs), particularly polystyrene variants (PS-M/NPs), have emerged as potential accelerators for the transformation of coexisting contaminants. This study uncovered a novel environmental phenomenon induced by aged PS-M/NPs and delved into the underlying mechanisms. Our findings revealed that the aged PS-M/NP particles significantly amplified the photodegradation of common cephalosporin antibiotics, and the extent of enhancement was tightly correlated to the molecular structures of cephalosporin antibiotics.
View Article and Find Full Text PDFSci Rep
January 2025
College of Horticulture and Plant Protection, Inner Mongolia Agricultural University, Hohhot, 010018, Inner Mongolia, China.
Pugionium cornutum (L.) Gaertn (P. cornutum) has strong tolerance to drought, salt and disease, but the tolerance mechanisms for such stresses in P.
View Article and Find Full Text PDFJ Photochem Photobiol B
January 2025
Department of Chemistry, Susquehanna University, 514 University Avenue, Selinsgrove, PA 17870, USA. Electronic address:
Photopolymerization of bovine serum albumin was carried out using reactive oxygen species (ROS) generated by the irradiation of citrate-stabilized gold nanoparticles by a pulsed Nd:YAG laser. The ROS in this case, singlet oxygen (O), targets aromatic amino acids within the protein to induce photopolymerization or crosslinking. Other ROS, like the hydroxyl radical, can also form in solution and under high-energy irradiation.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Environmental Science and Engineering, Nanjing Tech University, Nanjing 211816, China. Electronic address:
With the aid of radical and non-radical reactive species (RS), advanced oxidation processes can efficiently degrade emerging organic contaminants including antibiotics but may generate toxic transformation products (TPs). However, the detoxification capacity of popular RS has not been well elucidated. This study compared the detoxification of enrofloxacin (ENR) with three RS-dominated systems: O, SO+OH, OH.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
School of Environmental Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 611756, China. Electronic address:
Although hydroxyl radicals (OH) degrade organic pollutants nonselectively, their mineralization rate during the treatment of waste leachate biological treatment effluent (BTL) using Fenton or Fenton-like systems is not high, and the reason is unknown. In this study, we investigated three typical Fenton-like systems that act on dissolved organic matter (DOM) in BTL. We analyzed the molecular composition of DOM resistant to OH, using ultrahigh resolution mass spectrometry.
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